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HST

The Hubble Space Telescope (HST), a collaborative project between NASA and the European Space Agency, is a space-based observatory launched into low Earth orbit at an altitude of approximately 600 kilometers aboard the Space Shuttle Discovery on April 24, 1990, to conduct astronomical observations across ultraviolet, visible, and near-infrared wavelengths free from Earth's atmospheric distortion.^[1]^[2] Designed as a general-purpose instrument with a 2.4-meter primary mirror, it enables high-resolution imaging and spectroscopy that have yielded over 1.5 million observations, fundamentally advancing knowledge of cosmic phenomena such as galaxy formation, exoplanets, and the expansion rate of the universe.^[3]^[1] Key achievements include the confirmation of the accelerating expansion of the universe through measurements of distant supernovae, contributing to the 2011 Nobel Prize in Physics, and the discovery of thousands of exoplanets via transit photometry, reshaping planetary science.^[1] Hubble's deep-field images, capturing faint galaxies from the early universe, have provided empirical evidence for the Big Bang model and dark energy's role in cosmic evolution, with data supporting refinements to the Hubble constant that underpin modern cosmology.^[1] Despite reliance on ground-based precursors, its longevity—enabled by five astronaut-serviced missions—has sustained output exceeding initial projections, yielding peer-reviewed publications numbering in the tens of thousands.^[1] Initial operations were marred by a manufacturing defect in the primary mirror, causing spherical aberration that blurred images until corrective optics were installed during Servicing Mission 1 in December 1993, a repair that restored full functionality and exemplified causal engineering solutions over robotic alternatives debated at the time.^[4] Subsequent challenges, including gyroscope failures and computer anomalies, have prompted discussions of private servicing options, though NASA maintains single-gyro operations suffice for science until at least the mid-2030s, prioritizing cost-effective extension over risky interventions amid shifting priorities toward successors like the James Webb Space Telescope.^[1]

Individuals

Harry S. Truman

Harry S. Truman was born on May 8, 1884, in Lamar, Missouri, to John Anderson Truman, a farmer and mule trader, and Martha Ellen Young Truman; he was the eldest of three children.^[5] The family relocated to Independence, Missouri, in 1890, where Truman attended public schools and graduated from high school in 1901.^[5] Lacking funds for college, he held various jobs, including as a railroad timekeeper and bank clerk, before farming his family's land near Grandview for about 12 years starting around 1906.^[6] In 1917, Truman enlisted in the Missouri National Guard amid World War I, rising to captain of Battery D, 129th Field Artillery Regiment, and serving in France from 1918, where his unit fired over 10,000 shells in the Meuse-Argonne offensive.^[7] After the war, Truman partnered in a failed haberdashery in Kansas City from 1919 to 1922, accumulating debt during the postwar recession.^[6] He married Bess Wallace in 1919, whom he had known since childhood; they had one daughter, Margaret, born in 1924.^[5] Entering Democratic politics through Kansas City machine boss Thomas J. Pendergast, Truman was elected Jackson County judge in 1922 and presiding judge by 1926, overseeing infrastructure projects funded by county bonds despite later corruption scandals involving Pendergast.^[6] In 1934, he won a U.S. Senate seat, defeating the Pendergast machine's preferred candidate, and served on the Senate Special Committee to Investigate the National Defense Program, exposing waste in defense contracting during World War II preparation.^[6] Reelected narrowly in 1940 without Pendergast's tainted support, Truman gained national notice for his committee's efficiencies, saving an estimated $15 billion in expenditures.^[6] Truman was selected as Franklin D. Roosevelt's vice-presidential running mate in 1944 to balance the ticket amid intraparty divisions, winning election on November 7, 1944.^[6] He assumed the presidency on April 12, 1945, following Roosevelt's death from a cerebral hemorrhage, inheriting a nation at war and unaware of the Manhattan Project until briefed days later.^[8] Truman authorized atomic bombings of Hiroshima on August 6, 1945, and Nagasaki on August 9, 1945, leading to Japan's surrender on August 15, 1945, averting a projected 500,000 to 1 million U.S. casualties from an invasion of the Japanese home islands.^[8] At the Potsdam Conference from July 17 to August 2, 1945, he met Allied leaders to coordinate postwar Europe and demanded unconditional Japanese surrender.^[8] In foreign policy, Truman articulated the Truman Doctrine on March 12, 1947, pledging U.S. aid to Greece and Turkey against communist subversion, committing $400 million in assistance and marking a shift to containment of Soviet expansion.^[9] He oversaw the Marshall Plan, enacted as the Economic Cooperation Act on April 3, 1948, providing $13 billion (equivalent to over $150 billion today) for European reconstruction to prevent communist takeovers amid postwar economic collapse.^[10] The North Atlantic Treaty was signed on April 4, 1949, establishing NATO as a collective defense alliance against Soviet threats.^[11] Domestically, Truman's Fair Deal proposed expanded social programs, including national health insurance and civil rights measures, though Congress passed limited reforms like the Employment Act of 1946 creating the Council of Economic Advisers.^[10] He issued Executive Order 9981 on July 26, 1948, desegregating the U.S. military, effective by the Korean War's start.^[10] Truman authorized U.S. intervention in the Korean War on June 27, 1950, after North Korea's invasion of South Korea, committing UN forces under General Douglas MacArthur; Chinese entry in November 1950 led to stalemate, with armistice talks beginning in July 1951 and concluding July 27, 1953, after his term.^[8] Despite low approval ratings—around 22% by 1952 amid inflation, corruption scandals, and the firing of MacArthur on April 11, 1951, for insubordination—Truman won reelection on November 2, 1948, defeating Thomas E. Dewey in an upset, securing 303 electoral votes to Dewey's 189.^[11] He declined to seek a third term, leaving office on January 20, 1953, for Dwight D. Eisenhower. Post-presidency, Truman retired to Independence, establishing the Harry S. Truman Library in 1957, the first presidential library.^[12] His approval rebounded in later decades; by the 1970s, historians ranked him among the top ten presidents for decisive leadership in ending World War II and initiating Cold War strategies that contained communism without direct superpower conflict.^[11] Truman died on December 26, 1972, at age 88 from pneumonia complicating other ailments, in Kansas City, Missouri; he was buried beside Bess Truman, who died in 1982, at the Truman Library courtyard.^[5]

Hunter S. Thompson

Hunter Stockton Thompson (July 18, 1937 – February 20, 2005) was an American journalist and author recognized for originating gonzo journalism, a highly subjective reporting style that integrates the writer's personal experiences and biases directly into the narrative, often prioritizing visceral insight over detached objectivity.^[13]^[14] Born in Louisville, Kentucky, to insurance agent Jack Thompson, a World War I veteran, and homemaker Virginia, Thompson grew up in a middle-class family disrupted by his father's death from emphysema in 1952 and subsequent financial strain.^[15] As a teenager, he engaged in petty crime and skipped his high school graduation to avoid arrest, prompting his enlistment in the U.S. Air Force in 1956; stationed at Eglin Air Force Base in Florida, he served as sports editor for the base newspaper Command Courier until his honorable discharge as an Airman First Class in June 1958.^[16]^[17] Post-military, Thompson freelanced across the U.S. and Puerto Rico, honing his craft through sports writing and features for outlets like The National Observer. His immersion with the Hells Angels motorcycle gang from 1965 to 1966 yielded Hell's Angels: The Strange and Terrible Saga of the Outlaw Motorcycle Gangs, published by Random House in 1967, which detailed the group's culture, violence, and internal dynamics based on direct observation, though it ended with Thompson being beaten by members over a fee dispute.^[18] Gonzo journalism emerged in his 1970 Scanlan's Monthly piece "The Kentucky Derby Is Decadent and Depraved," co-illustrated by Ralph Steadman, where Thompson discarded notes and reconstructed events from memory and emotion; the term "gonzo," denoting frenzied eccentricity, was coined by editor Bill Cardoso to describe this approach.^[19] This evolved into Fear and Loathing in Las Vegas: A Savage Journey to the Heart of the American Dream, serialized in Rolling Stone in November 1971 and published as a book that year, chronicling a fictionalized drug binge in pursuit of the American Dream's remnants amid 1960s counterculture disillusionment.^[20] In 1970, Thompson launched the Freak Power movement in Aspen, Colorado, running for Pitkin County sheriff on a platform decriminalizing drugs, abolishing gambling, and prioritizing environmental conservation over development; he proposed shaving the heads of drug offenders and lost to incumbent sheriff Carrol "Red" Bennett by 463 votes despite mobilizing young voters.^[21] Subsequent works like Fear and Loathing on the Campaign Trail '72 (1973) applied gonzo to Nixon's reelection, blending reportage with invective against political hypocrisy. Residing at Owl Farm in Woody Creek, Colorado, from 1967 onward, Thompson sustained a lifestyle of firearms, substances, and isolation, contributing sporadically to Rolling Stone and ESPN until health decline, including chronic pain and a broken leg in 2003. On February 20, 2005, he died at age 67 from a self-inflicted .45-caliber gunshot to the head in his kitchen while on the phone with his wife, ruled a suicide by the Pitkin County coroner amid no evidence of foul play, though a 2025 review by Colorado authorities reaffirmed the original findings.^[22]^[23] His ashes were fired from a cannon at a 2005 ceremony attended by figures like John Kerry, symbolizing his defiant persona. Thompson's influence persists in experiential nonfiction, though critics note gonzo's potential for fabrication, as he admitted reconstructing lost notes rather than claiming literal accuracy.^[24]

Science and Astronomy

Hubble Space Telescope

The Hubble Space Telescope (HST) is a space-based observatory designed to capture high-resolution images and spectra in ultraviolet, visible, and near-infrared light, operating above Earth's atmosphere to avoid distortion from air turbulence and absorption. Launched on April 24, 1990, aboard Space Shuttle Discovery during mission STS-31, HST was deployed into low Earth orbit at an altitude of approximately 569 kilometers, completing about 15 orbits per day.^[1]^[25] Its primary mirror, with a diameter of 2.4 meters, enables angular resolution up to seven times sharper than ground-based telescopes of similar aperture, facilitating detailed studies of celestial objects from planets to distant galaxies.^[26] The telescope's development originated from a 1946 proposal by astronomer Lyman Spitzer for an orbital observatory, with formal NASA approval in the 1970s following congressional funding in 1977; construction concluded in 1985, though launch was delayed by the 1986 Challenger disaster.^[27] Early operations revealed a manufacturing defect in the primary mirror—a spherical aberration from incorrect grinding by 2.3 micrometers—rendering initial images blurry and reducing expected performance by a factor of 10 in some wavelengths.^[4] This flaw stemmed from a miscalibrated null corrector during polishing at Perkin-Elmer Corporation, as confirmed by post-launch interferometry.^[28] Correction occurred during Servicing Mission 1 (STS-61) in December 1993, when astronauts installed the Corrective Optics Space Telescope Axial Replacement (COSTAR), a set of corrective mirrors compensating for the aberration in fine guidance sensors and scientific instruments like the Faint Object Camera and Goddard High Resolution Spectrograph.^[4]^[29] Subsequent missions—SM2 in 1997, SM3A in 1999, SM3B in 2002, and SM4 in 2009—upgraded instruments, replaced failing components such as gyroscopes and solar arrays, and added the Wide Field Camera 3 for enhanced infrared and ultraviolet capabilities, extending HST's lifespan beyond initial projections.^[27] These interventions, conducted via spacewalks from shuttles like Atlantis and Endeavour, restored and improved optical performance, with COSTAR removed in 2009 after new instruments incorporated onboard corrections.^[30] HST's observations have yielded transformative data, including the Hubble Deep Field images from 1995 revealing thousands of galaxies in a seemingly empty sky patch, supporting estimates of the observable universe containing over 100 billion galaxies.^[1] It refined the Hubble constant measuring cosmic expansion to about 70 km/s/Mpc, contributed to supernova observations indicating accelerated expansion and evidence for dark energy, and helped determine the universe's age at 13.8 billion years through studies of globular clusters and cosmic microwave background correlations.^[31] Additional discoveries include the first direct images of extrasolar planet atmospheres, protoplanetary disks around young stars, and two moons of Pluto (Nix and Hydra) in 2005.^[31] As of 2025, HST continues joint operations with the James Webb Space Telescope, providing complementary wavelength coverage despite aging components like batteries and gyroscopes nearing end-of-life.^[1] Its dataset exceeds 1.5 million observations, archived publicly via the Mikulski Archive for Space Telescopes, underpinning thousands of peer-reviewed papers annually.^[32]

Health Sciences and Education

Harvard–MIT Program of Health Sciences and Technology

The Harvard–MIT Program in Health Sciences and Technology (HST), founded in 1970, represents the longest-standing collaboration between Harvard Medical School, the Massachusetts Institute of Technology (MIT), and affiliated teaching hospitals. It trains physician-scientists, biomedical engineers, and researchers by emphasizing quantitative foundations in biomedical sciences, translational research, and clinical expertise to drive innovations in diagnostics, therapeutics, and preventive medicine.^[33]^[34] HST offers an MD track through Harvard Medical School, structured for completion in four years with an optional fifth year for dedicated research, focusing on rigorous basic sciences, pathophysiology, and integrated clinical experiences that apply engineering approaches to patient care.^[34] The Medical Engineering and Medical Physics (MEMP) PhD program targets engineers and physical scientists, combining technical coursework, clinical immersion, and dissertation research at the nexus of engineering, biology, and medicine, often leading to joint MD-PhD pathways.^[35] Complementary programs include the Graduate Education in Medical Sciences (GEMS) certificate for current MIT PhD students, which bridges engineering with translational health applications, and a nine-week HST Summer Institute in Biomedical Optics for undergraduates pursuing hands-on research in imaging and photonics.^[36] Distinct from conventional medical curricula, HST prioritizes mathematical modeling, computational tools, and interdisciplinary problem-solving to address complex health challenges, fostering alumni contributions such as pivotal HIV/AIDS therapies and non-invasive neuroimaging techniques.^[33] Students engage faculty from diverse MIT and Harvard departments, leveraging resources like MIT's Institute for Medical Engineering and Science for collaborative projects grounded in empirical data and causal mechanisms of disease.^[33]

Computing and Telecommunications

High-Speed Technology (Modems)

High-Speed Technology (HST) was a proprietary modulation protocol developed by U.S. Robotics Corporation (USR) for dial-up modems, enabling data transmission rates exceeding contemporary standards in the mid-1980s. Introduced with the Courier HST modem in 1986, it utilized trellis-coded modulation to achieve full-duplex communication at 9,600 bits per second (bps) by asymmetrically allocating bandwidth: one direction operated at the full high speed while the reverse used a low-speed fallback of 300 bps, with the modems dynamically switching roles to simulate bidirectional flow.^[37] This "ping-pong" approach mitigated line noise and echo cancellation challenges inherent in symmetric full-duplex schemes, providing reliable connectivity over analog telephone lines prone to impairments.^[38] USR's HST modems gained prominence in the bulletin board system (BBS) era, where interoperability with non-proprietary standards was ensured through dual-standard designs that fallback to protocols like Bell 103/212A or V.22bis at lower speeds (up to 2,400 bps). The Courier HST model, priced around $795 in 1986, supported features such as automatic speed detection and error correction via Microcom Networking Protocol (MNP) levels 4 and 5, reducing retransmissions and effective throughput losses.^[39] By 1987, field tests demonstrated sustained 9,600 bps transfers over distances up to 10 miles on standard lines, outperforming competitors limited to 2,400 bps. HST's proprietary nature restricted peak speeds to USR-to-USR connections, fostering vendor lock-in but also innovation ahead of ITU-T standardization.^[40] Subsequent iterations expanded HST capabilities: in 1989, support reached 14.4 kbps; by 1992, 16.8 kbps; and later versions achieved 21 kbps and 24 kbps through enhanced trellis encoding and constellation mapping. Dual-standard HST modems, such as the Courier HST Dual Standard introduced around 1990, integrated V.32 compatibility at 9,600 bps, broadening market appeal as open standards like V.32bis (14.4 kbps, standardized in 1991) emerged. USR's emphasis on robust hardware, including Rockwell-compatible chipsets and asynchronous/synchronous modes, positioned HST modems as enterprise favorites for remote access and early Internet connectivity.^[41] However, the protocol's asymmetry introduced latency in direction switches (typically 100-200 ms), limiting real-world throughput in interactive applications compared to later symmetric standards.^[42] HST's legacy persisted into the 1990s, influencing modem design until superseded by V.34 (28.8-33.6 kbps) and V.90 (56 kbps downstream) as broadband alternatives diminished dial-up relevance. USR's acquisition by 3Com in 1997 commoditized remaining HST inventory, but the technology exemplified pre-standard innovation in overcoming analog channel limitations through proprietary signaling. Archival manuals and user reports confirm HST's role in enabling early high-volume data transfers, such as file sharing in pre-web networks, with effective rates often 20-30% above nominal due to compression and error control.^[43] Despite biases in retrospective tech histories favoring open standards, HST's empirical performance metrics—verified in period benchmarks—underscore its causal contribution to accelerating dial-up evolution.^[44]

Transportation

British Rail Class 43 High Speed Train

The British Rail Class 43 power cars, integral to the InterCity 125 High Speed Train (HST) sets, are diesel-electric locomotives designed for high-speed inter-city passenger services. Constructed by British Rail Engineering Limited (BREL) at Crewe Works between 1975 and 1982, a total of 197 units were produced to haul formations of Mark 3 coaches in a top-and-tail configuration.^[45] These power cars entered revenue service on 4 October 1976, initially on Western Region routes from London Paddington, marking a transformative advance in UK rail travel by enabling sustained speeds of 125 mph—far exceeding the 70-80 mph limits of contemporary express diesel locomotives—and thereby slashing journey times on key corridors.^[46] ^[47] Development of the HST stemmed from British Rail's need for faster, more efficient motive power amid competition from air and road transport in the early 1970s. Prototype power cars, classified as Class 41, emerged in 1972 and underwent extensive testing, achieving an early speed record of 143 mph in June 1973.^[48] Production models featured a streamlined, aerodynamic body designed by industrial designer Kenneth Grange, with integral mild steel construction, bogie-mounted air suspension, and disc braking for stability at high velocities.^[47] Each Class 43 unit mounts a Paxman Valenta 12RP200L turbocharged V12 engine delivering 2,250 bhp at 1,500 rpm, coupled to a generator supplying traction current to four GEC Traction or Brush DC motors—one per axle on its Bo-Bo wheel arrangement.^[47] The design prioritized reliability for intensive operations, with power cars capable of covering over 1,000 miles daily when paired with intermediate coaches.^[47] Operations expanded rapidly post-introduction, with HST sets dominating long-distance routes including the East Coast Main Line by 1978, where they monopolized services to destinations like Edinburgh for decades.^[46] In a notable demonstration of capability, power cars 43102 City of Wakefield and 43104, hauling three coaches, set a world record for diesel traction at 148 mph on 1 November 1987 during a test run between Northallerton and York.^[48] ^[49] Following British Rail privatization in the 1990s, the Class 43 fleet dispersed among private operators such as Great Western Trains, Virgin Trains East Coast, and later CrossCountry, with many undergoing re-engining to Paxman VP185 or MTU 16V 4000 units for improved fuel efficiency and emissions compliance—no original Valenta-powered cars remain in mainline passenger service.^[47] As of 2024, refurbished HSTs continue in secondary roles with operators like Grand Central, while others have been exported for use in Mexico, and select units preserved for heritage operations, underscoring the type's enduring mechanical robustness despite the advent of electric high-speed alternatives.^[47] ^[50]

Hypersonic Transport

Hypersonic transport encompasses conceptual and experimental aircraft designed for sustained atmospheric flight at speeds exceeding Mach 5 (greater than 1.7 km/s or 6,174 km/h at sea level), primarily for commercial passenger or cargo applications. Such vehicles would enable ultra-rapid global connectivity, potentially reducing transoceanic travel times to under two hours, but face profound engineering barriers including extreme aerodynamic heating, propulsion integration, and structural integrity. Unlike earlier supersonic transports like the Concorde, which operated at Mach 2 using turbojet afterburners, hypersonic designs rely on air-breathing engines such as scramjets that function without moving parts by compressing incoming air at supersonic speeds within the combustor.^[51]^[52] Historical efforts trace to the mid-20th century, with foundational research into hypersonic aerodynamics and ramjet propulsion emerging in the 1950s amid Cold War rocketry programs. The U.S. National Aero-Space Plane (NASP), initiated in 1986 as a joint NASA-Department of Defense project, aimed to develop a single-stage-to-orbit vehicle using hydrogen-fueled scramjets for both atmospheric and space access, but was terminated in 1993 after expending $2 billion due to insurmountable materials and weight issues under high thermal loads exceeding 2,000 K. Subsequent NASA X-43A scramjet demonstrator flights in 2004 achieved Mach 9.6 for 10 seconds, validating air-breathing hypersonic propulsion but highlighting limitations in sustained cruise.^[51]^[53] Contemporary development remains pre-commercial, dominated by government-funded research rather than viable passenger systems. NASA's Hypersonic Technology Project, ongoing since 2016, focuses on enabling routine reusable air-breathing flight through ground and flight tests of components like low-boom nozzles and thermal protection systems, with visions of integrated vehicles by 2050 serving as first-stage boosters. The European Space Agency's INVICTUS program, announced in July 2025, develops reusable hypersonic engines and a horizontal-launch testbed for atmospheric reentry, targeting initial flights by 2031 to support future space access vehicles adaptable to transport roles. Private ventures, such as those exploring scramjet-powered designs, project prototype tests around 2030, but no certified passenger aircraft exists, with progress tethered to military hypersonic advancements like boost-glide munitions.^[54]^[55] Key challenges include managing aero-thermal loads that cause air dissociation and plasma formation, necessitating advanced ceramics and active cooling systems; achieving efficient propulsion-airframe integration to avoid drag penalties; and mitigating environmental impacts like intensified sonic booms and fuel consumption rates far exceeding subsonic jets. Economic analyses suggest hypersonic transport could demand ticket prices 5-10 times current premiums due to high development costs (estimated at $10-20 billion per program) and operational complexities, rendering widespread adoption uncertain without breakthroughs in manufacturable high-temperature alloys and sustainable fuels. Despite optimism for point-to-point suborbital-like efficiency, empirical data from subscale tests indicate sustained Mach 5+ cruise remains unproven for manned vehicles, with failure modes like engine unstart posing risks.^[52]^[56]

Military and Defense

Helicopter Support Team

The Helicopter Support Team (HST) is a logistics element within the United States Marine Corps designed to enable helicopter-based cargo transport and support in expeditionary environments where ground mobility is limited or unavailable. HSTs facilitate the attachment, loading, and unloading of external loads on heavy-lift helicopters, such as the CH-53E Super Stallion, to deliver supplies, equipment, and personnel rapidly to remote or contested locations.^[57]^[58] Primarily staffed by Landing Support Specialists (Military Occupational Specialty 0481), HST personnel are trained in rigging techniques, landing zone preparation, and coordination with aviation crews to manage operations involving payloads up to 36,000 pounds. These teams integrate with combat logistics battalions and Marine Expeditionary Units to provide sustainment during deployments, including casualty evacuation and resupply missions in support of Special Purpose Marine Air-Ground Task Forces.^[59]^[60] HST training emphasizes proficiency in both daytime and nighttime exercises, simulating real-world scenarios such as external load extractions and vertical replenishment at forward operating bases. Units like the 1st Marine Logistics Group and 2nd Distribution Support Battalion conduct periodic drills at installations including Marine Corps Base Camp Pendleton and Okinawa's landing zones to validate procedures for safe helicopter integration with ground forces.^[57]^[61]^[62] In operational contexts, HSTs enhance Marine Corps maneuverability by bridging gaps in overland logistics, as demonstrated in exercises like Freedom Shield where teams managed helicopter landings for equipment delivery in austere terrain on December 9, 2024. This capability underscores the HST's role in distributed operations, prioritizing speed and reliability over fixed infrastructure.^[63]^[64]

Economics and Policy

Harmonized Sales Tax

The Harmonized Sales Tax (HST) is a consumption tax system in Canada that merges the federal 5% Goods and Services Tax (GST), a value-added tax, with a provincial sales tax component into a single rate applied and collected uniformly by businesses on most goods and services. Participating provinces cede administration to the federal Canada Revenue Agency, which collects the full HST and remits the provincial share, enabling full input tax credits for businesses on purchases—unlike traditional provincial sales taxes (PSTs), which often function as retail sales taxes without equivalent credit mechanisms and can lead to tax cascading. This structure reduces administrative burdens for multi-jurisdictional firms and minimizes distortions from separate federal-provincial filings.^[65]^[66] HST originated in the Atlantic provinces to address inefficiencies following the GST's 1991 introduction, which had layered a federal tax atop varying provincial regimes, complicating compliance. New Brunswick, Nova Scotia, and Newfoundland and Labrador adopted HST effective April 1, 1997, at a combined rate of 15% (5% federal GST plus 10% provincial), replacing prior separate collections where provincial taxes applied to prices inclusive of GST, exacerbating effective rates. Prince Edward Island followed on April 1, 2016, harmonizing its prior 5% GST and 9% PST into a 15% HST to simplify remittances and align with value-added principles. Ontario implemented HST on July 1, 2010, at 13% (5% GST plus 8% provincial), succeeding its 8% Retail Sales Tax; British Columbia briefly joined at 12% the same date but reverted to separate 5% GST and 7% PST on April 1, 2013, after public backlash and a referendum highlighted sector-specific rate sensitivities, such as on restaurant and construction services.^[67]^[68]^[69] As of 2025, HST applies in five provinces: New Brunswick (15%), Newfoundland and Labrador (15%), Nova Scotia (15%), Ontario (13%), and Prince Edward Island (15%), covering about 40% of Canada's population and generating combined revenues exceeding CAD 50 billion annually in recent fiscal years, with federal GST/HST collections reaching CAD 48.3 billion in 2022. Provinces retain flexibility via rebates, exemptions, or point-of-sale credits—Ontario, for instance, rebates the provincial portion on essentials like basic groceries and utilities to mitigate regressivity. Compared to non-harmonized areas (e.g., GST plus separate PST in British Columbia or Manitoba), HST eliminates dual audits and intergovernmental disputes over tax bases, though it initially raises visible consumer costs in transitioning provinces, prompting political resistance despite evidence of net administrative savings estimated at CAD 100-200 million yearly per province.^[70]^[71]^[72] Economically, HST aligns more closely with efficient value-added taxation by broadening the base and lowering effective rates through credits, reducing incentives for tax avoidance via exemptions and encouraging productive investment over consumption deferral—contrasting PSTs' narrower bases, which exempt business inputs unevenly and inflate costs in supply chains. Empirical analyses indicate harmonization boosts GDP by 0.5-1% over a decade in adopting provinces via simplified compliance, though short-term inflationary pressures and sector disruptions (e.g., housing in Ontario) have fueled repeal efforts; Nova Scotia, for example, temporarily cut its rate to 13% in 2010 before restoring to 15% amid revenue needs. Critics, often citing voter surveys over longitudinal data, argue higher headline rates deter tourism and retail, but causal evidence links separate PST-GST systems to higher evasion and deadweight losses exceeding 0.2% of GDP annually.^[66]^[73]^[74]

Hegemonic Stability Theory

Hegemonic Stability Theory (HST) maintains that periods of international economic and political stability depend on the presence of a dominant power, or hegemon, capable of providing global public goods such as open markets, a stable reserve currency, and security guarantees to underwrite cooperation among states.^[75] The theory posits that in an anarchic system lacking centralized enforcement, lesser states face incentives to free-ride on these goods, leading to underprovision and instability—such as trade wars or financial crises—absent hegemonic leadership.^[76] Hegemons bear disproportionate costs but gain relative advantages through systemic dominance, often enforcing rules via coercion or incentives rather than pure altruism.^[77] The theory emerged in the 1970s amid analyses of interwar economic disorder. Charles Kindleberger, in his 1973 book The World in Depression, 1929-1939, attributed the Great Depression's severity to the absence of a hegemon: Britain's economic primacy had eroded by World War I, while the United States, though ascendant, declined to assume stabilizing roles like lender of last resort or market opener until after 1945.^[78] Robert Gilpin extended this in works like War and Change in World Politics (1981), integrating realist elements by arguing that hegemons rise through innovation and superior capabilities but inevitably decline due to diffusion of power, overextension, or domestic constraints, prompting cycles of war and systemic change.^[79] Stephen Krasner further applied it to regimes like the gold standard, emphasizing how U.S. postwar hegemony facilitated institutions such as the Bretton Woods system (established 1944) and GATT (1947), which promoted trade liberalization and monetary stability until the 1970s.^[80] Empirical support draws from historical cases, including Britain's 19th-century hegemony, which underpinned the classical gold standard (adopted widely by 1870s) and global trade expansion, averaging 3-4% annual growth through naval enforcement of free navigation.^[81] Post-1945 U.S. dominance correlated with unprecedented stability: world trade grew from $58 billion in 1948 to $1.7 trillion by 1980, aided by dollar convertibility and military alliances like NATO (founded 1949).^[75] Assessments like Webb and Krasner's 1989 study find partial validation in regime persistence under hegemony but note inconsistencies, such as U.S. tolerance of deficits without immediate collapse.^[82] Critics challenge HST's causal claims, arguing stability often arises from institutions or mutual interests rather than unilateral dominance; for instance, European integration post-1957 proceeded without a clear hegemon, defying predictions of instability amid U.S. relative decline.^[83] Empirical tests reveal mixed results: hegemonic decline does not invariably trigger chaos, as seen in the post-1971 Bretton Woods erosion without global depression, suggesting overreliance on power distribution ignores ideational or domestic factors. Variants distinguish "benign" economic leadership (Kindleberger) from coercive political hegemony (Gilpin), but both face scrutiny for assuming hegemons prioritize system stability over self-interest, as evidenced by U.S. protectionist episodes like the 1980s voluntary export restraints on Japanese autos.^[84] Despite limitations, HST illuminates collective action dilemmas in international economics, where power asymmetries enable order amid incentives for defection.^[76]

Time Zones and Standards

Hawaii–Aleutian Standard Time

Hawaii–Aleutian Standard Time (HST) is a standard time zone defined as ten hours behind Coordinated Universal Time (UTC−10:00).^[85]^[86] The zone serves the state of Hawaii in its entirety and, within Alaska, the portion of the Aleutian Islands located west of 169°30′ west longitude, encompassing mostly uninhabited atolls and islands such as those near Attu. This time zone does not observe daylight saving time in Hawaii, which has maintained year-round standard time since ending wartime observance on September 30, 1945, due to legislative exemption under the Uniform Time Act of 1966.^[87]^[88] The Aleutian segments within the zone similarly remain on HST without seasonal adjustments, distinguishing them from eastern Aleutian areas reassigned to the Alaska Time Zone in 1983, which do advance clocks for Hawaii–Aleutian Daylight Time (HDT, UTC−09:00).^[87] The Hawaii–Aleutian zone originated from federal standardization efforts under the Standard Time Act amendments and Code of Federal Regulations (49 CFR Part 71), formalizing boundaries to align with geographic and administrative needs following Alaska's 1959 statehood and subsequent 1983 consolidations that preserved the western Aleutians' offset for solar alignment.^[89]^[90] Hawaii's consistent UTC−10:00 usage supports its equatorial latitude, minimizing seasonal daylight variation and rendering DST economically and practically unnecessary, as affirmed by state law prohibiting observance.^[87]

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When Harry S. Truman left the presidency in January 1953, he was one of the most unpopular politicians in the United States.
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Harry S. Truman: Life After the Presidency - Miller Center
Harry S. Truman died on December 26, 1972, of old age rather than any specific sickness. Bess vetoed plans for an elaborate state funeral and arranged an ...
[13]
Biography of Hunter S. Thompson, American Journalist - ThoughtCo
Dec 12, 2019 · Full Name: Hunter Stockton Thompson ; Known For: Journalist, writer, celebrity persona ; Born: July 18, 1937 in Louisville, Kentucky ; Parents: ...
[14]
Understanding Gonzo Journalism: From Thompson to Wolfe - 2025
Jun 7, 2021 · Thompson and the Origin of Gonzo Journalism. New Journalism was a creative non-fiction style of reporting developed in the 1960s and 1970s, ...
[15]
Hunter S. Thompson - Quotes, Books & Death - Biography
Apr 13, 2021 · Hunter Stockton Thompson was born in Louisville, Kentucky, on July 18, 1937. His father, Jack, was a World War I veteran and insurance agent ...Missing: major | Show results with:major
[16]
https://taskandpurpose.com/culture/hunter-s-thompson-air-force-press-release
[17]
Hunter S. Thompson - Carnegie Center
Kentucky Writers Hall of Fame · Born: Jul. 18, 1937 Louisville, Kentucky · Died: Feb. 20, 2005 Woody Creek, Colorado · Inducted : 2015.Missing: facts major
[18]
Hell's Angels by Hunter S. Thompson - Penguin Random House
In stock Free deliveryHunter S. Thompson's vivid account of his experiences with California's most notorious motorcycle gang, the Hell's Angels.
[19]
[PDF] Hunter S. Thompson and gonzo journalism: A research guide.
Hunter S. Thompson is the father of Gonzo Journalism. The article "The Kentucky Derby is Decadent and Depraved," published in Scanlan's Monthly, in June of ...
[20]
Fear and Loathing in Las Vegas by Hunter S. Thompson
$$18.00 Free delivery over $20 30-day returnsFirst published in Rolling Stone magazine in 1971, Fear and Loathing in Las Vegas is the best chronicle of drug-soaked, addle-brained, rollicking good times ...
[21]
'Freak Power': Inside Hunter S. Thompson's Run for Aspen Sheriff
Oct 23, 2020 · Co-directors Daniel Joseph Watkins and Ajax Phillips discuss 'Freak Power,' which follows Hunter S. Thompson's 1970 run for Aspen sheriff.
[22]
Hunter S. Thompson killed himself during phone call
Feb 26, 2005 · Hunter Thompson, famous for “Fear and Loathing in Las Vegas” and other works of New Journalism, shot himself in the head Sunday in the kitchen ...
[23]
Authorities give insight into review of Hunter S. Thompson's death
Oct 1, 2025 · On Feb. 20, 2005, Hunter Thompson died of “an alleged self-inflicted gunshot wound to the head” at his residence in Woody Creek, which the ...
[24]
On the Legacy of Hunter S. Thompson and Gonzo Journalism
Jan 5, 2022 · Gonzo journalism was an attitude, an experiment, and a withering critique of hypocrisy and mendacity. It began as an accident, peaked with several works of ...
[25]
Fact Sheet - ESA/Hubble
The Hubble Space Telescope is a joint ESA/NASA project and was launched in 1990 by the Space Shuttle mission STS-31 into a low-Earth orbit 569 km above the ...
[26]
Hubble Observatory - NASA Science
Launched on April 24, 1990 aboard the space shuttle Discovery, Hubble orbits roughly 320 miles (515 km) above Earth's surface. It completes 15 orbits per day, ...<|separator|>
[27]
Hubble Timeline - NASA Science
The complete timeline below describes Hubble's history from the first proposal of a space telescope by Lyman Spitzer in 1946, through the completion of Hubble' ...Hubble Servicing Missions... · Hubble Full History Timeline · Full Text
[28]
History: The Spherical Aberration Problem - ESA/Hubble
Hubble's main mirror being polished before installation. The edges were polished very slightly too flat, leaving the telescope unable to focus perfectly.Missing: controversies | Show results with:controversies
[29]
Servicing Mission 1 - ESA/Hubble
Aiming at correcting the optics of its flawed mirror shape and installing new instruments as part of a maintenance plan, the first Servicing Mission (STS-61) ...
[30]
Repairing Hubble | National Air and Space Museum
Apr 23, 2014 · During the various Hubble servicing missions, astronauts noticed tiny dimples and dents in the radiator – the result of space debris.Missing: controversies | Show results with:controversies
[31]
What has the Hubble Space Telescope discovered?
Since its 1990 launch, Hubble Space Telescope has been dazzling the world with images of space and a deeper understanding of how the universe works.
[32]
Hubble Space Telescope | STScI
The Hubble Space Telescope's launch in 1990 marked the beginning of a new era in humanity's exploration of the universe. From above Earth's obscuring ...Proposing · Approved Programs · HST Program Information · Zeropoints
[33]
About Us - Harvard-MIT Health Sciences and Technology
Founded in 1970, the Harvard-MIT Program in Health Sciences and Technology (HST) is one of the world's oldest interdisciplinary educational programs.
[34]
Health Sciences & Technology (HST) | Harvard Medical School
Jan 8, 2024 · Founded in 1970, the Harvard-MIT Program in Health Sciences and Technology (HST) is one of the world's oldest interdisciplinary educational ...
[35]
MEMP PhD Program | Harvard-MIT Health Sciences and Technology
HST's Medical Engineering and Medical Physics (MEMP) PhD program offers a unique curriculum for engineers and scientists who want to impact patient care.Biomedical and Clinical... · Neuroimaging Training Program · Concentration Areas
[36]
Academic Programs | Harvard-MIT Health Sciences and Technology
An HST education gives you a robust foundation in science, engineering, medicine, and scholarly research, along with the flexibility to explore the topics that ...
[37]
[PDF] USRobotics Courer HST Modem User's Manual - vtda.org
At top speed, data flows in one direction at 9600 bits per second and at 300 bits per second in the other. The modems automatically switch the high-speed ...
[38]
History of U.S. Robotics Corporation - FundingUniverse
Fast" protocol and a cellular modem system called HST Cellular (for "high speed technology"). This system would allow data transmissions over a cellular ...
[39]
COURIER MODEM A DAZZLING LEAP - Chicago Tribune
May 24, 1987 · ... HST modem means to the world of PC telecommunications. Of course, there`d be more to traveling 220 m.p.h. than simply changing the speed ...<|control11|><|separator|>
[40]
The Gadget We Miss: The US Robotics Courier Modem - Medium
Sep 5, 2013 · USR developed a technology called HST (High Speed Transfer), which was available only on their modems. If the BBS had this technology ...
[41]
[PDF] Courier High Speed Modems User's Manual 1.015.544 Rev B
This manual contains operating instructions for Courier V.32 bis,. Courier HST, and Courier HST Dual Standard modems. These modems have identical features ...
[42]
US Robotics Modems - Data Connect Enterprise
US Robotics was one of the first companies to offer high-speed dialup modems for PCs. The company quickly became a favored brand for PC manufacturers, ...
[43]
Definition of U.S. Robotics - PCMag
USR's HST protocol was a high-speed, reliable protocol before V.32bis became a modem standard in 1991. In 1997, USR became part of 3Com in the largest ...
[44]
A Brief History of Modems - Slashdot
Dec 26, 2009 · It was the USR Courier HST modem that would do 19.2kbps. I seem to recall there was a HST+2400 bps modem, and then the "Dual Standard" HST+ ...
[45]
https://www.hattons.co.uk/directory/vehicledetails/1002803/class_43_hst
[46]
Class 43 High Speed Train history - Key Model World
Jan 13, 2023 · On October 4 1976, exactly 40 years ago, a train that revolutionised rail travel in the UK first entered public service.
[47]
Best of British : BR Class 43 – High Speed Train - AROnline
Crewe Works 1984 – The HST required exacting maintenance with some sets operating in excess of 1000 miles a day! The prototype HST power car under construction ...
[48]
Trackside Classic: 1976 British Rail Inter City 125 High Speed Train
Oct 18, 2021 · And in November 1987, power cars 43102 City of Wakefield and 43104 with three coaches set a new world speed record for diesel traction of 148 ...
[49]
Celebrating a record-breaking HST - Harborough Rail Users
Feb 24, 2021 · This power car, partnered with sister 43159, achieved the world speed record for a diesel train, on a test run between Northallerton and York on 1st November ...
[50]
British Rail class 43 (High Speed Train) - loco-info.com
They significantly shortened travel times compared to trains with conventional diesel locomotives. With a record of 148.5 mph (239 km/h), they are considered ...<|separator|>
[51]
[PDF] Facing the Heat Barrier: A History of Hypersonics - NASA
Hypersonics is the study of flight at speeds where aerodynamic heating dominates, typically Mach 5 and higher.
[52]
[PDF] Hypersonics: Past, Present, and Potential Future - Johns Hopkins APL
Hypersonic technologies have been investigated for more than six decades, and important operational capabilities exist in the form of reentry, space lift, and ...
[53]
Hypersonic Flight Vehicles – Introduction to Aerospace ... - Eagle Pubs
During the 1980s, NASA began considering a single-stage hypersonic flight vehicle as a replacement for the Space Shuttle. The National Aerospace Plane (NASP) ...
[54]
Hypersonic Technology Project - NASA
NASA is working to enable routine, reusable, airbreathing hypersonic flight by conducting fundamental and applied research.Missing: ESA | Show results with:ESA
[55]
INVICTUS – Europe's new hypersonic test platform - ESA
Jul 16, 2025 · A research programme with the goal of developing hypersonic technologies applicable to future reusable vehicles capable of horizontal launch.
[56]
Hypersonic Technology Project Overview - NASA
Jun 21, 2024 · By 2050, NASA envisions the development of a next-generation reusable hypersonic vehicle that could serve as the first stage in a two-stage ...Missing: ESA | Show results with:ESA
[57]
https://www.marines.mil/News/Marines-TV/videoid/661102/
[58]
CLB-15: Helicopter Support Team - Marines.mil
May 31, 2023 · The helicopter support team is responsible for the rapid transportation of cargo via helicopter when it cannot be transported by ground or needs ...
[59]
https://www.marines.mil/News/Marines-TV/videoid/358386/
[60]
The Heavy Lift Helicopter and Its Role in Supporting Diverse USMC ...
Apr 21, 2025 · The heavy lift helicopter supports USMC operations by providing sustainment, lifting up to 36,000 pounds, and transporting equipment, troops, ...<|control11|><|separator|>
[61]
2nd Distribution Support Battalion Helicopter Support Team ... - DVIDS
Sep 14, 2025 · U.S. Marines with 2nd Distribution Support Battalion, Combat Logistics Regiment 2, 2nd Marine Logistics Group, conduct helicopter support ...
[62]
Video - 3rd LSB Helicopter Support Team Training - DVIDS
Jan 28, 2025 · ... helicopter support team (HST) exercise at landing zone Swan, Okinawa, Japan, Dec. ... Military 24/7 Logo · US Deptartment of Defense Logo.
[63]
3rd LSB Helicopter Support Team Training - Freedom Shield
Dec 9, 2024 · ... helicopter support team (HST) exercise at landing zone Swan, Okinawa, Japan, Dec. 9, 2024. HST are operations conducted to train landing ...
[64]
The Marine Corps' Newest Expeditionary Radar System Performs ...
Aug 7, 2025 · A helicopter support team of logistics specialists and landing support Marines with Combat Logistics Battalion 8, Combat Logistics Regiment ...
[65]
Canada - Corporate - Other taxes - Worldwide Tax Summaries
Jun 13, 2025 · Unlike GST/HST, PST is not a VAT (it is a retail sales tax) and is not recoverable. Therefore, any PST paid on purchases by a business cannot ...
[66]
The Goods and Services Tax: 10 Years Later(PRB 00-03E)
Newfoundland and Labrador, New Brunswick and Nova Scotia apply a single sales tax of 15% – the harmonized sales tax (HST) – which includes the PST and GST. It ...
[67]
The Daily, Thursday, May 15, 1997
May 15, 1997 · Six provinces introduced sales tax changes in late March and April. Newfoundland, Nova Scotia and New Brunswick merged their provincial ...
[68]
Ontario and British Columbia: Transition to the Harmonized Sales Tax
The Government of Ontario and the Government of British Columbia have each introduced a harmonized sales tax (HST) that came into effect on July 1, 2010.Missing: Atlantic PEI
[69]
HST - A Quick Guide for Small Business Owners - 777Taxes
Mar 1, 2024 · The introduction of the Harmonized Sales Tax in three Atlantic provinces in 1997 combined the federal GST and provincial sales taxes. The ...
[70]
GST/HST Statistics Tables (2018 to 2022 calendar years) - Canada.ca
Jun 9, 2025 · The goods and services tax/harmonized sales tax (GST/HST) statistics tables provide detailed profiles of GST/HST registrants by jurisdiction ...Missing: impact | Show results with:impact
[71]
Harmonized Sales Tax | ontario.ca
Mar 23, 2022 · Currently, the Harmonized Sales Tax is 13% in Ontario. However, Ontario provides a rebate on the 8% provincial portion of the HST on specific ...Retail Sales Tax · HST: Ontario point-of-sale... · HST: Ontario First Nations rebateMissing: impact | Show results with:impact
[72]
Sales Tax Rates by Province - Retail Council of Canada
As of July 1, 2016 the HST rate increased from 13% to 15%. Northwest Territories, GST, 5%, 5%. Nova Scotia, HST, 14%, 14% ...Missing: economic impact
[73]
GST vs. HST: Which Is Better for the Canadian Economy?
Jul 19, 2024 · Both GST and HST have advantages and disadvantages in terms of audit service. GST is simple and uniform, while HST is efficient and provides more revenue for ...
[74]
GST HST PST - What's the Difference? - BorderBuddy
Apr 1, 2021 · The system of GST, HST, and PST is unique to Canada. It differs from both European VAT and American sales tax.
[75]
Hegemonic stability theory: an empirical assessment
Oct 26, 2009 · Hegemonic stability theory, which argues that international economic openness and stability is most likely when there is a single dominant state.
[76]
[PDF] The Theory of Hegemonic Stability - LSE
The neo-realist version of hegemonic stability theory sees interests as deriving from the position of individual states in the world economic structure.
[77]
https://oxfordre.com/politics/display/10.1093/acrefore/9780190228637.001.0001/acrefore-9780190228637-e-552
[78]
[PDF] A Modified Theory of Hegenmonic Stability. - DTIC
The inception of the hegemonic stability theory came from Charles. Kindleberger (1973). Kindleberger bases his argument on the necessity of a single state to ...
[79]
[PDF] THE THEORY OF HEGEMONIC STABILITY ... - EA Journals
1 Kindleberger, Charles, P.,“ Dominance and Leadership in the International Economy ... Hegemonic Stability Theory: An Empirical Assessment”,. Review of ...
[80]
[PDF] Theories of International Regimes - Harvard DASH
Several efforts have been made to confront hegemonic stability theory with altemative expla- nations. Joanne Gowa resorts to domestic factors and ...
[81]
[PDF] Charles Thompson The Impact of British Hegemony on World Trade ...
A good example of empirical work is done in Michael C. Webb and Stephen D. Krasner in their 1989 article titled “Hegemonic Stability Theory: An Empirical ...Missing: definition proponents criticisms
[82]
Hegemonic Stability Theory: An Empirical Assessment - jstor
This paper is an attempt to assess the empirical validity of the hegemonic stability ... literature review. It is a study of trends in the international political ...
[83]
Revisiting the fallacies in Hegemonic Stability Theory in light of the ...
Dec 10, 2019 · This paper revisits, from a conceptual angle, the shaky basis upon which the theory draws a causal link between hegemony and stability.Missing: peer- | Show results with:peer-
[84]
[PDF] UMI - OhioLINK Electronic Theses and Dissertations Center
One of the strongest criticisms made of hegemonic stability theory is that a hegemonic state promotes free trade but seems to get very little in exchange for ...Missing: origins proponents
[85]
Local Time FAQs | NIST
Sep 16, 2024 · What are the time zones in the United States? ; Alaska (AKT), AKST -9, AKDT -8 ; Hawaii-Aleutian (HT), HST -10, HDT -9 ; Samoa (ST), SST -11, --- ...
[86]
U.S. Time Zones
Hawaii-Aleutian daylight time (HDT), subtract 9 hours from UTC. Hawaii-Aleutian standard time (HST) ... time was repealed in 1919, but standard time in time zones ...Missing: usage regions
[87]
Daylight Saving Time | US Department of Transportation
Sep 3, 2025 · Daylight Saving Time is not observed in Hawaii, American Samoa, Guam, Northern Mariana Islands, Puerto Rico, the Virgin Islands, and most of Arizona.
[88]
Daylight Saving Time
Not all places in the U.S. observe Daylight Saving Time. Hawaii and most of Arizona observe standard time only. Many countries observe some form of "summer time ...
[89]
49 CFR Part 71 -- Standard Time Zone Boundaries - eCFR
The seventh zone, the Hawaii-Aleutian standard time zone, includes the entire State of Hawaii and, in the State of Alaska, that part of the Aleutian Islands ...
[90]
History of Time Zones and Daylight Saving Time (DST)
Jan 17, 2023 · Five time zones were officially adopted as the US entered World War I: the Eastern, Central, Mountain, Pacific, and Alaska zones, all of which are still in use ...Missing: offset | Show results with:offset